1. Field of the Invention
The present invention relates to an angle detecting device having a combined structure of two resolvers.
2. Description of Related Art
In order to have redundancy to reduce the risk of failure in an angle detecting device, a structure is disclosed in Japanese Unexamined Patent Application Laid-open No. 2006-250864, for example. In this structure, two resolvers are coaxially arranged in an axial direction. In addition, although it is not constructed to have the redundancy against failure, a resolver provided with two laminated stators is disclosed in Japanese Unexamined Patent Applications Laid-open Nos. 2005-164486 and 2005-345454.
According to the structure disclosed in Japanese Unexamined Patent Application Laid-open No. 2006-250864, two resolvers are simply coaxially combined. Therefore, two sets of the parts for the resolvers must be prepared, and the entire structure is not simple. In addition, an assembly process is complicated, thereby increasing the production cost. According to the techniques disclosed in Japanese Unexamined Patent Applications Laid-open Nos. 2005-164486 and 2005-345454, output windings are serially connected and form one resolver as a whole, whereby the redundancy against failure is not obtained.